Pentax K-3 vs Pentax 645Z

Cameras
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Pentax K-3 vs Pentax 645Z

APS-C 366.6mm²
24.4 megapixels
ISO 100 - 51,200

Go in depth with our full Pentax K-3 Review.
How does it shoot? Pentax K-3 in the real world.
See real-world photos taken with the K-3.
Compare Pentax K-3 image quality against competitors.
What’s the bottom line? Read our Pentax K-3 conclusion.

Medium format 1,436.6mm²
51.4 megapixels
ISO 100 - 204,800

Go in depth with our full Pentax 645Z Review.
How does it shoot? Pentax 645Z in the real world.
See real-world photos taken with the 645Z.
Compare Pentax 645Z image quality against competitors.
What’s the bottom line? Read our Pentax 645Z conclusion.

Succeeded by the Pentax K-3 II
Compare K-3 vs K-3 II
Compare Pentax K-3 II vs Pentax 645Z

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Differences

Pentax K-3 advantages over Pentax 645Z

Lens selection
Excellent vs Limited
Better lens selection gives you more options
In-Camera Image Stabilization
Yes vs No
Reduces the effects of camera shake at slower shutter speeds
Fast startup
~0.90 vs 1.5 sec
Faster startup lets you catch the moment
Internal flash
Internal flash vs None
Useful in a pinch for fill flash
Thinner
77 mm vs 123 mm
Thinner
Headphone jack
Yes vs No
Monitor audio recording while you shoot video
Optional anti-aliasing filter
Optional vs None
Lets you choose sharper photos or reduced moiré
Faster JPEG shooting
7.1 fps vs 3.1 fps
Faster JPEG shooting (burst mode)
Bigger JPEG buffer
75 vs 12 shots
Take more JPEG shots before waiting (burst mode)
Faster RAW shooting
7.1 fps vs 3.1 fps
Faster RAW shooting in burst mode
Bigger RAW buffer
24 vs 10 shots
Larger buffer for RAW shots (burst mode)
Faster shutter
1/8000 vs 1/4000 sec
Shoot wide open in bright light

Pentax 645Z advantages over Pentax K-3

Larger sensor
Medium format vs APS-C
More sensor area. Bigger is (generally) better.
Bigger pixels
~ 5.31 vs 3.91 microns
Better low-light and dynamic range (all else equal)
Tiltable Screen
Tiltable vs Fixed
Tilt the screen for shooting flexbility
Higher effective ISO

Higher effective ISO

Maximum effective ISO is an estimate of the highest sensitivity at which a camera can capture excellent quality photos.

Cameras with higher effective ISO will be better choices for indoor photography, night shooting, and indoor sports photography, especially if you intend to make large prints.

You can learn more at our glossary entry.

Maximum effective ISO test data courtesy of DxO Mark.
645Z test data on DxO Mark K-3 test data on DxO Mark

4,505 vs 1,216 iso
Take photos in low light with less noise
More viewfinder magnification
0.78x vs 0.63x
Get a bigger view of the scene through the eye-level viewfinder
More pixels
51.4 vs 24.4 megapixels
Higher resolution photos
Higher extended ISO
204800 vs 51200 ISO
Higher extended ISO can give more low-light flexibility

Similarities

Common Strengths

Focus peaking
Both provide
Your camera will highlight what's in focus
Eye-level viewfinder
Both provide
You'll be able to frame photos even when the sun is out
Top deck display
Both provide
Check settings with a screen on top of the camera
External Mic Jack
Both provide
Improved sound fidelity when shooting video
HDMI out
Both provide
Use HDMI output to monitor or review video
Hot shoe
Both provide
Off-camera flashes open new possibilities
Dual card slots
Both provide
Gives you more storage flexibility
Bulb shutter
Both provide
Hold the shutter open manually for long exposures

Common Weaknesses

Tilt-swivel screen
Neither provide
Tilt and swivel the screen for maximum shooting flexibility
Touchscreen
Neither provide
Interact with your camera just like your smartphone
In-camera panoramas
Neither provide
Stitches multiple shots into a panoramic photo
Built-in Wi-Fi
Neither provide
Share your photos wirelessly
NFC
Neither provide
Simplifies pairing your camera with supported phones
Built-in Bluetooth
Neither provide
Always-on wireless connectivity
Built-in GPS
Neither provide
Geotag your photos
On-sensor phase detect
Neither provide
Usually improves live view and video AF performance
Slow-motion videos
Neither provide
Shoot slow-motion videos

User reviews

Amazon
Adorama
Read K-3 User Reviews

Amazon
Adorama
Read 645Z User Reviews

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Buy the Pentax K-3

Body Only

Body Only
Kit with 18-135mm Lens

Your purchases support this site

Buy the Pentax 645Z

Body Only

Review Excerpt

Top-notch image quality; Great ergonomics in a compact body; Unique on-demand low-pass filtering; Broad sensitivity range; Large and bright viewfinder for an APS-C camera; Dual card slots; Optional Wi-Fi remote control
AE Lock button is poorly located; Below-average battery life for a DSLR; Rather dated-looking menu system; Requires a different battery grip accessory than its predecessors; Less third-party support than some rivals
Read our Pentax K-3 Review

Phenomenal resolution and detail; Great high ISO performance; Rugged, weather-sealed body; Huge, bright viewfinder; Fast autofocus works well in low light; Swift performance for a medium-format camera; Good battery life; Shoots Full HD video
Quite bulky compared to an APS-C or full-frame DSLR; Autofocus points clustered near center of frame; Most lenses aren't weather-sealed or optimized for digital; Prone to aliasing artifacts (but so are most high-end cameras these days); Attracts a lot of attention from passers-by
Read our Pentax 645Z Review

The Competition

Compared to Pentax 645D

Pentax K-3

Pentax 645D

$699
APS-C

Lens selection
Focus peaking

$3599
Medium format

Larger sensor
Bigger pixels

Compare Pentax K-3 vs Pentax 645D

Pentax 645Z

Pentax 645D

$4845
Medium format

Focus peaking
Tiltable Screen

$3599
Medium format

Fast startup
Longer stills battery life

Compare Pentax 645Z vs Pentax 645D

Compared to Nikon D7100

Pentax K-3

Nikon D7100

$699
APS-C

Focus peaking
In-Camera Image Stabilization

$695
APS-C

Fast startup
Longer stills battery life

Compare Pentax K-3 vs Nikon D7100

Pentax 645Z

Nikon D7100

$4845
Medium format

Focus peaking
Larger sensor

$695
APS-C

Lens selection
Less expensive

Compare Pentax 645Z vs Nikon D7100

Compared to Nikon D5300

Pentax K-3

Nikon D5300

$699
APS-C

Focus peaking
In-Camera Image Stabilization

$549
APS-C

Tilt-swivel screen
Fast startup

Compare Pentax K-3 vs Nikon D5300

Pentax 645Z

Nikon D5300

$4845
Medium format

Focus peaking
Larger sensor

$549
APS-C

Lens selection
Less expensive

Compare Pentax 645Z vs Nikon D5300

Compared to Leica S-E (Typ 006)

Pentax K-3

Leica S-E (Typ 006)

$699
APS-C

Lens selection
Focus peaking

$16900
Medium format

Larger sensor
Bigger pixels

Compare Pentax K-3 vs Leica S-E (Typ 006)

Pentax 645Z

Leica S-E (Typ 006)

$4845
Medium format

Focus peaking
Tiltable Screen

$16900
Medium format

Built-in GPS
Thinner

Compare Pentax 645Z vs Leica S-E (Typ 006)

Compared to Nikon D7200

Pentax K-3

Nikon D7200

$699
APS-C

Focus peaking
In-Camera Image Stabilization

$1043
APS-C

Fast startup
Built-in Wi-Fi

Compare Pentax K-3 vs Nikon D7200

Pentax 645Z

Nikon D7200

$4845
Medium format

Focus peaking
Larger sensor

$1043
APS-C

Lens selection
Less expensive

Compare Pentax 645Z vs Nikon D7200

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